Closure for containers and a method of making it



Aug. 12, 1969 BEDER ET AL I 3,460,709

CLOSURE FOR CONTAINERS AND A METHOD OF MAKING IT Filed Aug. 25. 1966 INVENTORS GERT GOTTFRIED BIEDER HERBERT WALTER ZIESAK KURT GERHARD KUHN United States Patent i 3,460,709 CLOSURE FOR CONTAINERS AND A METHOD OF MAKING IT Gert Gottfried Bieder, Detroit, Mich, and Herbert Walter Ziesak, Braunschweig, and Kurt Gerhard Kuhn, Broistedt, Germany, assignors to J. A. Schmalbach AG., Braunschweig, Germany, a corporation of Germany Filed Aug. 23, 1966, Ser. No. 574,368 Int. Cl. B65d 43/02 US. Cl. 220-47 1 Claim ABSTRACT OF THE DISCLOSURE A closure for a package container, for example, a can for preserves, consists of an elastic removable sealing ring provided with a tab and clamped between the edge of the container cover and an outwardly curved edge of the container body. The closure is characterized in that the sealing ring is placed under tension directly below the rounded edge of the body, while a rolled edge flange which is substantially completely closed, is provided in the edge portion of the cover which is bent toward the container body. This rolled edge flange engages the sealing ring only by an outer surface directed toward the container body in order to change the shape of the ring.

This invention relates to a lock for containers such as cans for preserves as well as to a method of manufacturing such lock. The invention is particularly concerned with a can provided with a removable elastic ring which is normally clamped between the edge of the cover and the edge of the cover body and is provided with a grip or strap.

Cans of this type which are known in prior art have the advantage over the usual cans with fold-over covers in that they can be opened without the use of any tool whatsoever. To open the container the user merely pulls the grip downwardly in an inclined direction. Then the ring is freed from its seat and the cover can be removed.

Prior art cans of this type have, however, various drawbacks, It was found, for example, in a construction in-which a straight cover edge extends around the elastic ring that there is the possibility that the lock may open up when this is not desired, since the edge of the cover is not suificiently rigid. In another construction in which an elastic rectangular ring is clamped into a flange edge of the cover, the resistance against an unintended opening of the container is greater due to the provision of the flange, but then comparatively largepulling forces are required for the opening of the container. Furthermore, in this construction the fixing of the ring in the cover requires a special comparatively complicated operation which increases the cost of manufacture. All of these constructions have the common drawback that the edge of the can cover must be of special design and that the covers are of a shape which makes it impossible to pile them one on top of the other so that they cannot be used in machinery wherein piled up covers are used.

An object of the present invention is the provision of a can closure which will eliminate the drawbacks of prior 3,460,709 Patented Aug. 12, 1969 position and located directly below a flange of the edge of the container body, the ring being at least partly enclosed and compressed by a substantially closed inner edge of the flange of the cover. This construction eliminates to a great extent the sharp edges which hinder the pulling out of the ring for the opening of the can. On the contrary, in this construction, during the opening procedure, the ring slides along the round inner side of an inner flange of the cover without being subjected to any substantial resistance, the forces required for the fitting being quite small. The provision of this inner edge furthermore removes to a very great extent the danger that the can or container may open unintentionally.

According to a further advantageous feature of the present invention the inner flange has an oval shape in cross section, for example the shape of an ellipse or the outline of an egg, and is slightly bent over the ring, since this greatly facilitates the opening of the can by pulling of the elastic ring. The elastic ring is preferably circular in cross section.

In addition to the above-described advantages, the present invention has the further advantage that the cover can consist of the usual folded cover, such as the one set forth in the norm 2040 of the German Industry Norms, which covers can be conveniently stapled one over the other and do not require any special tools for their manufacture.

The ring can be fixed in 'a manner known per se, either by a fold located in the container body below its edge or by being clamped at the edge of the container body in a manner which is also known. The first construction will be preferred in the case of a container or can con sisting of three parts, namely, for a container wherein the lock with the elastic ring is completely finished by the can manufacturer, whereupon another concern fills the containers with the required contents through the open bottom and subsequently closes the bottom in the usual manner by a cover. The second construction is preferably used when the can consists of two parts, namely when the can body and the bottom are made of one piece by a drawing operation. In that case the can manufacturer takes over the somewhat more complicated operation of clamping the ring upon the can body while the other concern fills the can from the top and carries out the closing operation by using the can covers which have been supplied separately.

The process of the present invention which is required to manufacture the cans proceeds in the same manner in both above-described cases, namely, the cover is placed upon the opening of the can, then the rolled edge is shaped so as to provide a substantially closed inner flange and thereupon the edge surface of the cover along the inner flange is placed at least partly around the fixed elastic ring which is located below the outer flange of the container body. Theoretically the step of forming the closed flange of the edge could be carried out before the cover is placed upon the container. Practical experience has shown, however, that such a procedure may not be satisfactory for the subsequent piling of the covers; furthermore, it requires a separate intermediate tool device. Preferably the edge of the cover along with inner flange is placed over the ring to such an extent that the flange presses against the ring.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawing, showing by way of example, preferred embodiments of the inventive idea.

In the drawing:

FIGURE 1 is a section through an upper portion of a container manufactured in accordance with the principles of the present invention on a greatly enlarged scale.

FIGURE 2 is a partial section of the usual cover which is to be used as a part of the closure constituting the subject of the present invention.

FIGURE 3 is a partial section illustrating the possibility of fixing the ring upon the container body by means of an outer bead.

FIGURE 4 is a similar partial section showing another possibility of fixing the ring wherein, however, the con tainer body does not have an outer rounded flange but merely a projecting edge.

FIGURE 5 is a similar partial section illustrating the possibility of clamping the ring by means of the round flange of the container body.

, FIGURES 6a, 6b and 6c illustrate, in that sequence, the three steps necessary for forming the closure of the present invention of the type shown in FIG. 3.

The containers shown in the drawings have a body 1 which is preferably made of a thin sheet metal. In the constructions shown in FIGS. 1, 3, 6a, 6b and 6c, the container body 1 terminates in a round flange 2 whereby the flange 2 is formed by a curved inwardly extending edge.

On the other hand, in the construction shown in FIG. 4 the body of the container has the regular edge 2.

In all constructions an elastic ring 3 is located directly below the upper edge of the container body 1 and is fixed thereon. The ring 3 which is used for the opening of the can or container is provided for this purpose with a tab 4.

The fixing of the ring 3 has the purpose of preventing the sliding or the dropping of the ring during the closing operation. In accordance with the present invention this fixing of the ring can be carried out in two ways.

The first method of fixing the ring is illustrated in FIGS. 1, 3, 4, 6a, 6b and 60. According to these embodiments an outwardly extending ridge 5 is provided in the container body below the upper edge of the body so that the ring 3 engages the ridge 5 from the top. This manner of holding the ring is preferably used in so-called threepart cans, namely, in cans wherein the bottom is applied separately to the can.

It is also possible to replace the annular ridge 5 by several small projections located upon the same level and distributed upon the can surface.

A second procedure of holding the ring which is illustrated in FIG. 5, consists in that the curved rounded flange 2 of the container body is used to clamp the ring. This manner of holding the ring is preferred for so-called two-part cans, namely, cans wherein the container body and the bottom consist of one part.

In accordance with the present invention rings 3 of any desired cross section can be used. It is possible to use round, oval or rectangular rings.

In the construction of FIG. 5 a ring 3' is provided with an upwardly extending lobe 3a which can be clamped by the flange 2 of the container body.

The cover 6 of the container of the present invention is the usual cover which is manufactured for example, in accordance with the norm 2040 of the Norms of the German Industry. The cover 6 includes the usual edge surface 7 which ends in a rolled end portion 8. The end portion 8 actually is formed as a practically closed inner curved portion 8', as shown in FIGS. 1 and 6b. This shaping takes place before the can is completely sealed by the cover 6.

FIG. 1 shows a completely closed can wherein the edge portion 7 of the cover 6 including the inner flange 8' is moved over the ring 3 in such manner that the ring is at least partially enclosed by the cover edge portion and so that the flange portion 8" presses against the ring only by its surface 9 directed toward the container body and somewhat changes the shape of the ring. Despite this change in shape the cover can be easily and conveniently opened since, when the ring 3 is pulled downwardly by means of the tab 4, it does not contact any sharp edges which could prevent the easy pulling of the ring.

FIGS. 6a, 6b and 6c illustrate the process of producing the closure of the present invention. These figures show a closure container provided with an annular supporting ridge 5. The process of clamping the ring proceeds in the same manner as the process shown in FIG. 5, wherein the ring 3' is clamped by the edge 2 of the-container body. Initially the ring'3 is placed over the container body 1 and then moved to the position in which it is supported from below by the ridge 5. Then the cover 6 is placed loosely upon the container, asshown in FIG. 6a. Thereupon a tool is used to change the open bent edge 8 of the cover 6 into a closed inner flange 8' which is shown in FIG. 6b and which is preferably oval or elliptical in cross section. FIG. 60 shows the further step of'the process, consisting in that the edge portion 7 together with the inner flange 8' is moved over the ring 3 whereby the flange 8' is pressed into the ring.

As already stated, the container of the present invention can be easily opened by pulling the tab 4 downwardly and at an angle. This pulling loosens the ring 3 from its position so that the cover 6 can be easily removed.

It is possible to use other geometric shapes of the closure than those shown in FIG. 1. For example, depending upon the construction and use of the closure tools, the inner flange 8 can be made round. Furthermore, the edge surface 7 does not have to be rounded as shown in FIG. 1, but can remain flat. All such and other variations and modifications are to be included within the scope of the present invention.

What is claimed is:

1. A closure for a container having an open body with an outwardly directed edge enclosing the opening of said body and an outwardly extending ridge located below said edge, said closure comprising a cover for closing said opening and an elastic ring enclosing, under tension, said body and engaging said edge and said ridge, said ring being clamped between said edge and said ridge, and a tab connected with said ring, said cover comprising an edge portion curved outwardly and then inwardly toward said body and having a substantially closed oval flange bent in the direction toward said ring and having an outer surface pressing against a side surface of said ring, said flange engaging said ring and pressing against it solely with said outer surface, the edge of said flange being devoid of contact with said ring.

References Cited UNITED STATES PATENTS 3,224,627 12/1965 Dielmann et al. 220-47 JAMES B. MARBERT, Primary Examiner US. Cl. X.R. 215-46 

